Social Security Number (SSN) and Individual Taxpayer Identification Number (ITIN)

General Information

Foreign national individuals, both resident aliens and nonresident aliens, may have either a Social Security Number (SSN) or an Individual Taxpayer Identification Number (ITIN)

A Social Security Number (SSN) is:

  • A nine-digit number assigned by the Social Security Administration to an individual for tax and wage reporting purposes

An Individual Taxpayer Identification Number (ITIN) is:

  • A nine-digit number assigned to an individual who is required to have a tax identification number, but who is ineligible for a Social Security Number

  • The ITIN is for tax reporting purposes and/or for claiming tax treaty benefits

NOTE: A nonresident alien who wishes to claim exemption from tax withholding under a tax treaty MUST have an SSN or ITIN

Social Security Number (SSN)

How do I apply for an SSN?

If eligible, you will need to complete Form SS-5 Application for a Social Security Card, and go to your local Social Security Administration Office. Harvard sponsored foreign nationals can seek guidance from the Harvard International Office.

Individual Taxpayer Identification Number (ITIN):

The ITIN does not:

  • entitle the recipient to social security benefits

  • indicate immigration status

  • give the right to work in the U.S.

The ITIN cannot be used in place of an SSN (if eligible for the latter) for tax and wage reporting.

How do I apply for an ITIN?

Submit a completed IRS Form W-7 Application for IRS Individual Taxpayer Identification Number, along with documentation to substantiate your foreign status and true identity, to the IRS. Harvard sponsored foreign nationals can seek guidance from the Harvard International Office.

Where do I obtain the IRS Form W-7 application for an ITIN?

Obtain IRS Form W-7 from the IRS web site.


The information contained within this website is provided for informational purposes only and is not intended to provide, and should not be relied on for, tax, legal or accounting advice.  All information in this site is provided "as is", with no guarantee of completeness, accuracy, timeliness or of the results obtained from the use of this information, and without warranty of any kind, express or implied, including, but not limited to warranties of performance and fitness for a particular purpose.